A stare made its way to Seulgi. It was Irene who was staring at her.

Irene accepts the fact that she can't be with Seulgi anymore but she just want to at least stare at her. 

Staring is all she can do, after all, because she has lost Seulgi long time ago. 

Seulgi was now happy with Krystal. They have been together for years already, unlike Irene who was with Seulgi for months only.

The insane similarity is that both Irene and Krystal fell hard for Seulgi.

Seulgi liked Irene, loved her, even. But now, she's with Krystal because of Irene's own doing.

Irene wasn't able to make up her mind on who she likes until Seulgi got really tired of it and so she made a decision to just move on from Irene.
 

She kept having flings until Krystal. Krystal waited for her and that's enough for them. Enough for them to fall in love so hard. So hard that even when Irene just look at them together, her heart aches to the point she can almost feel it getting broken into pieces.

And so, staring is the furthest she can do because Seulgi is with someone who she loves. Someone who's not Irene. 

Insanely, it's all because of Irene's own doing.